All documents referred to herein, or the indicated portions, are hereby incorporated by reference herein. No document, however, is admitted to be prior art to the claimed subject matter.
Highly sophisticated instruments have been developed for performing complex assays requiring multiple process steps to be performed simultaneously and independent of each other. Such instruments can be used to perform chemical analyses, immunoassays, molecular-based tests, and the like. The most advanced of these instruments are capable of performing sample-to-result, nucleic acid-based amplification tests (“NAAT”) that allow for walk-away testing. See Friedenberg et al., “Developing a Fully Automated Instrument for Molecular Diagnostic Assays,” IVD Technology (2005) 11(6):47-53; Hill, “Automating Nucleic Acid Amplification Tests,” IVD Technology (2000) 6(7):36-45. Fully automated NAAT testing reduces the chances for contamination or user error and is increasingly important because of a national shortage of medical technologists trained to conduct more complex assays, such as NAAT tests. With full automation, the instrument performs all the necessary steps of an assay with minimal human intervention. For NAAT assays, these steps include processing of raw samples to extract one or more nucleic acids of interest and to separate the nucleic acids from potentially interfering materials; performing an amplification reaction, such as polymerase-based extension reaction, to increase the sensitivity of the assay (e.g., TMA, SDA or PCR); and detection of the nucleic acids of interest. In general, however, instruments used to perform NAAT assays are not easily portable and their usefulness is typically limited to large-scale testing in controlled environments. Therefore, a need currently exists for a compact system capable of performing sample-to-result, NAAT assays in point-of-use testing, such as in field testing or bedside medical applications.